Its gigantic size, varying from about 4 to 7 inches in expanse of
wings, together with its bright colors, makes it an easily remembered
insect. The scientific name of this moth (Samia cecropia) is the first
scientific name of an insect that many of us can recall learning. The
time of active flight is at night, and thus it is that they are so
frequently found in numbers about electric lights to which they have
been attracted by the intense light. Their rather awkward flight and
large size often lead to their being mistaken for bats.
The differences between the sexes are not so manifest as in Promethea,
yet it is not difficult to distinguish them. The females are larger
and have stouter bodies, but the most conspicuous difference is that
the "feelers" or antennae of the male are feather-like and very large
and broad, while those of the female are only about one-half as broad.
The eggs are somewhat flattened, about one-tenth of an inch long,
pale in color, and are deposited by the female in small patches upon
a large variety of plants, since there are about fifty of these upon
which the larvae will feed. The eggs usually hatch in about a week or
ten days, the young larvae being very different in appearance from
the mature ones. The changes in appearance are brought about by five
moults or sheddings of the skin. The full-grown larva is pale green or
light blue, 3 or 4 inches long, armed with eight more or less complete
rows of large tubercles. Those above on the second or third thoracic
segment, are bright red; all the others are yellow except those on the
sides of the body and on the first thoracic and last body segment,
which are blue. Unfortunately, these colors soon fade in the dead larva
as is seen in the plate. This wonderful development of tubercles seems
to be in some way related to the arboreal habits of the larvae.
Although a variety of parasites which prey upon these larvae is not
large, they are very numerous in individuals, and it is to this cause
that only a small per cent of the larvae ever produce moths. These
parasites develop beneath the skin of the larva as footless grubs,
which, at first, do not attack the vital organs, but later these organs
are preyed upon, and the larva dies. A wasp-like insect which preys
upon this larva well illustrates in its habits the crudeness of many
instincts. The female will lay eight or ten eggs upon one caterpillar,
but as the young parasitic grubs require a large amount of food, only
one is able to mature and the others perish.
[Illustration: PROMETHEAN MOTH.
(Callosamia promethea)
Adult Male. Adult Female.
Larva. Pupa. Cocoon.
CECROPIAN MOTH.
(Samia cecropia.)
Pupa.
Adult Male. Eggs on Maple Leaf. Adult Female.
About 1/2 Life-size.
Larva. Cocoon.
COPYRIGHT 1900 BY
A. W. MUMFORD, CHICAGO.]
The insect parasites seem, in many cases, to mature and transform
into the adult stage after the caterpillar has built its cocoon, and
thus many parasites lose their lives, since they are not always able to
escape from the cocoon. A cocoon will sometimes be found filled with
these small insects, which have not been able to make their escape, and
have thus died in prison.
The adult larva, unlike Prometha, usually spins its cocoon not attached
to a leaf, but along a stem; sometimes, however, they may be placed in
other situations.
In about two weeks after the cocoon has been spun, the larva transforms
into a chrysalis, in which stage it hibernates during the winter, and
from which it emerges in May or June.
During the winter, when the leaves are not on the trees and shrubs
which are frequented by these larvae, a large number of cocoons may
easily be collected. These should be kept out of doors during the
winter, for if kept in a warm room they will emerge during the winter
or so early in the spring that food cannot be secured for the larvae.
If one secure a number of old cocoons, from which the moths have
failed to emerge, and cut them open longitudinally, he may learn many
interesting facts. A dead and dry mummified looking larva or chrysalis
may be found, or, what is even more interesting, no trace of the larva
or chrysalis may be present, but only a mass of small white, paper-like
cocoons. These have been left by a colony of little wasp-like parasites
which may occur in such large numbers that there is scarcely room for
all to spin their cocoons, so that on account of being so closely
crowded together, they are moulded into a mass of cocoons having the
form of the cavity formerly occupied by the larva.
The cocoons of Cecropia are composed of two parchment-like layers of
silk which are generally very dense and strong. The space between
these two layers contains loosely spun threads of silk like a layer of
packing material. The larvae seem normally to make three varieties of
cocoons; one kind is very loosely constructed, much larger than the
ordinary form and not attached to a twig, but found in the grass or in
shrubs near the ground. The two other forms of cocoons are much smaller
and more closely woven, but differ in size; female moths as a rule
emerging from the larger cocoons, and males from the smaller ones.
Dead larvae are sometimes found in cocoons which are practically of
a single thickness; there being no space between the outer and inner
layers. The hollow skins of the larvae found in such cocoons clearly
show that this unusual cocoon is due to the influence of parasites upon
the larva.
In the upper open end of the cocoon, kernels of wheat, corn, beechnuts
and even acorns have been found. How these get in this position seems
to be quite a puzzle. In opening twenty or thirty cocoons, five or six
kernels of corn have been found, thus showing that this occurrence is
by no means rare. Chickadees and blue-jays have been given the blame
for this work, since these birds are thought to have the habit of
hiding food. The inverted outer layer of the cocoon clearly shows, in
some cases, that the kernel of corn has been thrust into the cocoon
with some force.
The head of the pupa lies at the small end of the cocoon, where the
texture is less dense, and thus, when it is ready to transform into the
moth, the head is in the best position for easy escape from the cocoon.
But this provision alone is not sufficient to make sure the escape. At
the time of emergence, the pupa secretes a fluid which escapes from
the mouth and by moistening the cocoon softens the glue-like material
which binds together the threads, thus making it possible for the
freshly emerging moth to crowd its way between the fibres, and thus
secure its freedom. When the moth first crawls out of the cocoon,
its heavy body and small folded wings show but little resemblance to
the fully-expanded moth. By degrees, however, the wings expand and
become more rigid, the colors brighten, and finally the mature moth is
developed.
The Promethea Moth is only about one-half the size of Cecropia, and the
two sexes are very different in appearance; so much so that one would
not at all think they were the same kind of moths. As in Cecropia the
male moths are somewhat smaller than the females, and the antennae
show the same kind of differences, i.e., the antennae of the males are
much larger and feather-like. In color, the sexes of Cecropia are much
alike, but in this moth the differences in color are very great, the
dominant color in the female being a reddish brown, while that in the
male is a very dark-brown or almost black. Thus these moths furnish an
excellent illustration of what is called sexual dimorphism, a term used
for those animals in which the sexes are very different in appearance,
a subject to which Charles Darwin gave considerable attention, in his
"Descent of Man."
The female moth lays her cream-colored eggs, which are a little smaller
than those of Cecropia, upon shrubs and trees in clusters of five or
six. The small larva usually hatches in about ten days, and feeds upon
the leaves of ash, sassafras, lilac, tulip tree, maple, cherry, and a
number of other trees and shrubs, but it is much more select in the
choice of its food than Cecropia. The larvae have voracious appetites,
devour many leaves and grow at a correspondingly rapid rate. The
differences between the very young and the adult larva, aside from that
of size, are very great. On account of the very limited elasticity of
the skin, this larva, like other insect larvae, only increases in size
after shedding. This is periodically accomplished by throwing off the
old skin, which prevented expansion, and by growing a new and larger
one. Promethea has from three to five of these moults, the number being
influenced apparently by climate, since southern larvae have more
moults than northern ones. The time between these moults varies from
two days to a week.
The leaves upon which the larvae feed may have long or short petioles.
A singular account has been given of how these larvae have overcome the
difficulties associated with feeding upon long-petioled leaves. There
is considerable risk of falling and of the leaf breaking away when a
large larva crawls out upon a slender petiole. The larva avoids these
risks and yet reaches the blade of the leaf. This is accomplished as
follows: The larva grasps firmly the branch with its posterior legs;
reaches out a considerable distance along the petiole, and bites it
through in several places. This causes the leaf to droop; the larva now
reaches out, seizes the drooping leaf, and draws it within convenient
reach, where it can be eaten at leisure. This is a wonderful display of
instinct, yet it is not infallible, because at times the petioles are
eaten too far through, and when they droop, break completely away and
fall to the ground.
When ready to spin its cocoon, the adult larva is about two inches
long; these cocoons are very different from those of Cecropia. As a
rule, they are found suspended from a branch by a silken cord, the
length of which depends upon the length of the petiole of the leaf in
which the cocoon was spun. Thus if the leaf has only a short petiole,
this cord is also short, but if the petiole is two or three inches
long, the suspensory cord is correspondingly long. The larva in
constructing its cocoon, first spins a strong band around a twig, and
binds the petiole of the leaf to the stem; this band extends down the
petiole to the cocoon, and thus anchors it. The cocoon proper, or the
part occupied by the chrysalis, is spun in a folded leaf. When this
leaf dies and rots away, the cocoon hangs freely suspended by the cord,
but it is very evident that the cocoon has been moulded in a leaf by
the prints of the veins which remain upon it. A valve-like opening
occurs in the upper end, through which the moth emerges.
The wings of the chrysalis are very small as compared with those of
the adult moth; are folded to the body on the under side, and covered
by the pupal skin. During the winter they remain transparent since
there are at this time none of the rich colors present which are later
found in the moth. About ten days before the moth emerges the wings
become white, a few days later definite colors begin to appear on the
under side of the wings between the veins. While in the adult moths the
colors in the two sexes are very distinct, at this time their wings
are very similar. The wings do not long retain this similarity, but
gradually become more and more unlike until maturity.
Breeders of moths have often noticed that there is considerable
uniformity with regard to the time of day at which certain kinds of
moths emerge. For Promethea this time seems to be in the forenoon.
From an extensive series of experiments, it has been learned that the
male finds his mate by means of scent and that this is doubtless the
explanation for the very large antennae of the male, since it is in
these organs that the sense of smell is located.
Although it may be very interesting to read about the activities of
insects, a much more fascinating side of the subject is to handle and
study the insects themselves, and there are but few better insects with
which to begin a personal acquaintance than these which we have been
considering.
Charles Christopher Adams.
A PLEA FOR LEGISLATIVE PROTECTION.
In former numbers of Birds and Nature we have seen how much our welfare
and happiness depends upon the birds. Some hints have been given as
to how we may encourage the birds to become residents of our premises
so that we may enlist them in the constant warfare against worm and
weevil. If there were no great and universal interest at stake in this
question, How much do we owe to the birds? we should, perhaps, have
no right to go beyond simple encouragement to the birds to multiply
and do their good work in certain chosen places. But the interests
are universal and so deeply concern the whole world that we have an
undoubted right to say to those who would kill everything in sight,
either for gain or for so-called "sport," Thou shalt not! In other
words, we have the right to make laws forbidding anybody to kill birds
except for the best of reasons. This right has been acted upon in
most states and in many foreign countries, where various degrees of
protection to the birds as well as to other animals have been secured.
But in very many, if not in most cases, the laws enacted have not
furnished protection enough. Those who have put a price upon a bird's
plumage, who furnish the temptation for others to break the law against
killing birds, have not had a check put upon them. And the class of
"sportsmen" which regards anything living (except man and some of
the domestic animals) as legitimate targets for their weapons, have
not been dealt with severely enough. Even where the laws have seemed
prohibitive enough they have often failed of their purpose because not
properly enforced. There are, then, two things to be considered. First,
the passage of laws that will be prohibitive, and, second, machinery
adequate to their enforcement.
The first question will then be, How may we secure the passage of laws
such as we need? Certainly not by waiting for the state legislatures to
do it. In such matters, at least, they wait for an expression of the
people. Then agitate the question until the time is ripe for presenting
it before the lawmakers of your state and push it. Write to Mr. Witmer
Stone, the chairman of the American Ornithologists' Union, chairman
of the Committee on Bird Protection, for a copy of the ideal law, and
then act in line with other states. If each state acts in accord with
some plan for the whole country, we shall have practically a national
protective law. But even this community of interest will not accomplish
the purpose for which we set out, even as a law, saying nothing of
enforcement. All this is directed against the killing of birds. The law
must prohibit the sale of the bird or any part of its plumage for any
purpose. Carefully guarded exceptions or privileges might be favorable
to those who need material for strictly scientific study. But it is
necessary to go even further than this. We shall not accomplish our
purpose until a law is enacted prohibiting the importation of feathers,
whether on the skin or separated from it. If we are not yet ready to
say that no feathers may be imported, then let us absolutely prohibit
the importation of any part of any species of our native birds,
whether killed in America or anywhere else. That much lies within our
power. Evidently we are not yet ready to say that birds, or parts
of birds--meaning our native birds--shall not be worn as an article
of dress. We need a long campaign of education before that will be
feasible.
What, now, of the enforcement of these laws? Clearly the enforcement of
any law must have behind it a public sentiment demanding enforcement. A
law fails to be prohibitive when it receives only indifferent attention
from the public for whom it was passed. It is our privilege to so bring
to the attention of the people at large their own great interests,
which are dependent upon the birds, that their eyes shall be opened
to see the great necessity of prompt and united action. The great
growth of popular interest in the birds during the past three years is
the clearest proof that the time is now ripe for such a campaign of
education. Push it now. In every mind there lies dormant an interest
in nature which needs but a touch now to be awakened to activity and
usefulness.
But there is still the machinery of enforcement to be considered, for
however much the general public may be educated there will always be
some persons, not a small number, we fear, who must be held in check by
legislative action. In the first place, game wardens are too few, in
most counties, to properly enforce the laws. They should be numerous
enough and so situated that they may be reached readily. But if this
increase in number be not practicable, then there is a way out of the
difficulty. We must be more active ourselves. In a large majority of
cases we shall have no need to cause arrests, but need only to inform
the transgressor of the existence of the law, giving him some useful
information of the great good which the birds do, and of the pleasure
which may be gained from a study of the living bird, and the purposes
of the law will be accomplished. For many times the transgressor is
of foreign birth, knowing nothing of the esteem in which we hold the
birds. Or else the person is simply thoughtless, or ignorant of the
law and its purposes. The other cases of flagrant breaking of the law
need and deserve prompt and severe treatment. Here it is often not a
matter of education but of discipline. It is not pleasant to be an
informer, but such cases should be put upon a par with any other sort
of law-breaking, for there is a great public interest involved beside
which our own personal interest, however great that may be, sinks into
insignificance. It is a duty which we have no right to shirk.
To summarize the means by which we may hope to secure adequate
protection for our rapidly decreasing birds: Legislative action brought
about by combined effort throughout the country; enforcement of the
laws enacted by an increase in the public interest, by an increase of
the number of game wardens, by our own activity in seeing that the laws
are enforced. By these means we may accomplish what we undertake.
Lynds Jones.
* * * * *
The little bird sits at his door in the sun,
A tilt like a blossom among the leaves,
And lets his illumined being o'errun
With the deluge of summer it receives;
His mate feels the eggs beneath her wings,
And the heart in her dumb breast flutters and sings;
He sings to the wide world, and she to her nest,
In the nice ear of Nature which song is the best?
--James Russell Lowell, "The Vision of Sir Launfal."
[Illustration: IRISH SETTER.
COPYRIGHT 1900, A. J. PICKERING.
CHICAGO:
A. W. MUMFORD, PUBLISHER.]
THE DOG AND ITS ANCESTORS.
That the domestic dog has been held in high esteem by mankind from
the earliest times, is shown by written records and mummified remains
obtained from countries situated widely apart. The statement occurs
in the Zendavesta, that "the world exists through the intellect of
the dog." Cuvier wrote that "the dog is the completest, the most
singular and the most useful conquest that man has ever made * * * each
individual is devoted to man and remains attached to him even unto
death; and all this springs not from necessity nor from fear, but from
a true friendship. The dog is the only animal that has followed man all
over the globe."
Egyptian monuments dating back 3,400 years B. C., show several
varieties of dogs, most of them being allied to the greyhound. Carved
records of a later period portray the mastiff, a turnspit and a form
closely resembling the hound. Without question the dog was domesticated
in Europe previous to any historical record. His remains are found in
the kitchen-middens of Neolithic times and an increasing size in the
animals is noticed through the Bronze and Iron ages in Denmark. Remains
of the Neolithic in Switzerland disclose skulls closely resembling our
hounds, setters or spaniels. The Americans had indigenous dogs before
the conquering Spaniards introduced European species, and mummies of
dogs are found in the oldest Peruvian tombs.
All this goes to show that the differentiation of the dog took place
at a very early date. As in the case of man, the link is missing, but
the ancestry is certain. Without question the varieties of the dog
originated in domestication and inter-breeding of different species of
wolves living in various parts of the world.
The dog family is divided into three groups. First, the wolves or wild
dogs, having a round pupil in the eye and a short tail. Second, the
foxes, which are characterized by a slit-like pupil and a long bushy
tail; and, third, the long-eared dogs which inhabit eastern deserts
and possess more numerous and a different set of teeth than the other
groups. Considered as a family they are distinguished by a lean body,
small head, the slim or long legs terminated by small paws furnished
with strong but not retractile claws. The fore paws usually have five
toes while the hind paws are always limited to four. As the dogs do
not live exclusively on animal food they are not as savage as the
cats, neither do they possess the "soulless expression of face so
characteristic of the felidae."
While most of the dog family are gregarious, certain forms lead lives
that are solitary or nearly so. Other species are nocturnal in their
habits, while yet others burrow in the earth for shelter or protection.
All bend the joints of the legs in walking, all possess great speed and
endurance, and without exception are good swimmers.
Intellectually, dogs are more highly developed than any other brute
animal. Many forms act with a rational deliberation and follow
carefully thought-out plans. The senses are wonderfully developed. The
sense of smell is marvelous in many forms, while strength of eyesight
distinguishes others.
Of the three groups mentioned, the wolf without question was the
ancestor of the domestic dog. In the German mythology, he was
consecrated to the god Woden, but when Christianity reconstructed
old beliefs, Woden was metamorphosed into "The Wild Hunter," and the
wolves became his attending dogs, which finally were evolved into the
ghost-like wolves of nursery and fable. The wolf has all the attributes
of the dog except the nobility which necessarily comes from education.
The tail always droops, never curling upwards as in the domestic dogs,
and even when tamed they rarely wag the tail. Among the wolves may be
mentioned the jackals of Asia, which are said to have entered largely
into the breeds of oriental dogs. These were known to the ancients as
"gold wolves," and are said to be the foxes whose tails Samson set on
fire in order to burn the fields and vineyards of the Philistines. The
Indian wild dog, or "Kolsun" is claimed by many to be the progenitor of
all domesticated dogs. He closely resembles a greyhound, and is found
all over the Himalaya and East India country. He exhibits many traits
characteristic of our hunting dogs.
Prominent among several distinctive and familiar breeds of dogs is the
Greyhound, which while graceful and universally popular as a pet, and a
sporting dog, is unfaithful and unsympathetic. The great lung capacity
gives the animal unusual endurance, but while possessed of keen sight
and hearing, the sense of smell is very deficient. The Mastiffs
constitute another group embracing many of the familiar forms. Among
these are the Danish dog, the German Mastiffs, the Bulldog and the Pug.
With the exception of the Pug, which is justly called a caricature of a
dog, the group is remarkable for fidelity, courage, determination and
strength. Great Britain is the home of the Hounds which, because of
their intelligence and docility, are considered to be in the first rank
of domestic dogs. All the varieties of this group are born hunters,
being strong, swift and possessed of unusually keen senses, especially
that of smell. Among these are the Pointers, the German Bloodhounds,
the Staghounds, the Beagles, and the Foxhound. This last is justly
considered the greatest of hunting dogs, possessing the speed of the
greyhound, the courage of the bulldog, the delicate scent of the
bloodhound and the sagacity of the poodle, he is well equipped for his
duties in field and forest.